He played college football for the Texas Longhorns and was selected by the New England Patriots in the first round of the 2015 NFL draft.

[5] Sources: Brown played in all 13 games as a true freshman at the University of Texas at Austin in 2012, recording 25 tackles.

He finished the year with 68 tackles and two sacks, and won the team's Joseph W. Moore Tenacity Award for Defense along with Jackson Jeffcoat.

[12] After his junior season, Brown decided to forgo his senior year in an effort to declare for the 2015 NFL draft.

[29] On May 2, 2018, the Patriots declined the fifth-year option on Brown's contract, making him a free agent at the end of the season.

[33] Brown finished the season with 32 total tackles, four quarterback hits, 1.5 sacks, one pass defended and one fumble recovery.

[34][35] In Week 9 of the 2020 season against the Tampa Bay Buccaneers, Brown recorded a sack on his former Patriots teammate Tom Brady during the 38–3 win.

[41] In 2024, Brown became the head football coach at St. Dominic Savio Catholic High School in Austin, Texas.